Oh, there is no right or wrong answer. It doesn't matter what a foetus has more in common with, it IS a human, and even if people object to war so much, then think about this. War = people killing people. Abortion = people killing babies. When it's put like that, which sounds worse? I am firmly against war and abortion. But aborton is the topic, so I'm going to stick with that.
When you have an abortion, you destroy a child. You destroy their right to grow up, speak their first word, take their first step. You stop them falling in love, getting married, having their own kids, watching them grow old, and of course, the inevitable, death. Could anyone actually live with knowing that they'd killed a child?
Even if there are those circumstances that make people want to have an abortion, like financial conditions, marital status, anything else. There is NO excuse for murder. Because that's what it is. Murder.